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#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define EPS 1e-9
#define mod 1000000007
// #define mod 998244353
#define over 10000000000
#define sz(m) (ll)(m.size())
#define ceil(n, m) (((n) / (m)) + ((n) % (m) ? 1 : 0))
#define fixed(n) fixed << setprecision(n)
const ll inf = 1e18 + 5;
// vector< vector <int> > nums( n , vector<int> (m)) ;
//  priority_queue<int, vector<int>, greater<int> > pq ;
template <typename T = int>
istream &operator>>(istream &in, vector<T> &v)
{
  for (T &i : v)
    in >> i;
  return in;
}
template <typename T = int>
ostream &operator<<(ostream &out, const vector<T> &v)
{
  for (const T &x : v)
    out << x << ' ';
  return out;
}

void lol()
{
  ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
#ifndef ONLINE_JUDGE
  freopen("input.txt", "r", stdin), freopen("outputt.txt", "w", stdout), freopen("error.txt", "w", stderr);
#endif
}
double log(double base, double x)
{
  return (log(x) / log(base));
}

int dx[4] = {1, 0, 0, -1};
int dy[4] = {0, 1, -1, 0};

/////////////////////////////////////////////////////////

int kmp(string &s)
{
  int n = s.size();
  vector<int> fail(n);
  int k = 0;
  for (int i = 1; i < n; i++)
  {
    while (k > 0 && s[k] != s[i])
    {
      k = fail[k - 1];
    }
    if (s[k] == s[i])
      k++;
    fail[i] = k;
  }
  return fail.back();
}

int main()
{
  lol();
  string s;
  while (cin >> s)
  {
    string x;
    string rv = s;
    reverse(rv.begin(), rv.end());
    x = rv + '#' + s;
    int sm = kmp(x);
    for (int i = s.size() - sm - 1; i >= 0; i--)
    {
      s += s[i];
    }
    cout << s << '\n';
  }
}